DE102004023240A1 - Device and method for Balgrestdruckregelung - Google Patents

Abstract

The present invention provides a bellows pressure control apparatus comprising: an air spring device (100, 101) having an air bladder (100) for carrying loads; a valve (103), which is connected by pressure to the air bellows (100), for sealing or venting the air bladder (100); a pressure detection device (102) which is connected by pressure to the air bellows (100) for detecting the actual pressure in the air bellows (100); and electronic control means for actuating the valve (103) in response to the difference between a stored SETPOINT pressure and the ACTUAL pressure. The present invention further provides methods for ball-gap pressure control.

Description

The The present invention relates to an apparatus and a method for Balgrestdruckregelung, especially in air-suspension vehicles, such as for example, trucks.

vehicles with an air suspension device, such as container or interchangeable vehicles, are sometimes strong in their daily use Load changes suspended. When unloading the load by means of a Cranes may experience the problem that the vehicle body is abrupt freed from the cargo load, the vehicle body against Ausfederungsanschläge can drive. These are an increased risk of destruction and thus one exposed to significant reduction in life. Therefore It required that the load be very much like that of a crane operator Gently and slowly raised to allow plenty of time to disposal stands to the bellows to vent the vehicle.

One Another problem arises when the entire vehicle of a Crane is raised. A complete Rebound of the bellows can then cause them to pop out of their holder. Upon subsequent weaning of the vehicle, the bellows may become leaking or wrinkles form in places which are not for wrinkling are provided. Such wrinkling can be normal Roll off the bellows and thus severely restrict the air suspension or To block.

A well-known air suspension device for vehicles with a mechanical quick exhaust and residual pressure protection in the bellows is in the German Offenlegungsschrift DE 40 17 876 A1 described. For quick exhaust, a quick exhaust valve with residual pressure protection is provided between a level control valve and the air spring bellows, whereby the residual pressure is mechanically adjustable via a set screw with tension spring.

Other lifting and lowering devices on or for air suspension vehicles are in the DE 100 03 045 A1 , WO 01/21422 A1 and the DE 102 27 453 A1 described.

In front It is therefore the object of the present invention to provide this background underlying, an improved quick exhaust for air suspension device specify.

According to the invention this Task by a device for Balgrestdruckregelung with the features of claim 1 and by a method for Balgrestdruckregelung solved with the features of claim 6.

Accordingly, it is provided:
A device for Balgrestdruckregelung, in particular in air-suspension vehicles, comprising: an air spring means for resiliently supporting loads, which comprises an air bellows; a pressure-technically coupled to the air bellows, electrically controllable valve for sealing or for aeration or venting of the air bladder; a printing technology coupled to the air bellows pressure detecting means for detecting an actual pressure in the air bellows; and electronic control means for driving the valve in response to the difference between a stored SETPOINT pressure and the ACTUAL pressure. (Claim 1)

• (a) Ermitteln eines IST-Druckes in einem Luftbalg einer Luftfedereinrichtung;
• (b) Vergleichen des IST-Druckes in dem Luftbalg mit einem SOLL-Druck, welcher in einer elektronischen Speichereinrichtung bereitgestellt wird;
• (c) Belüften des Luftbalgs über ein elektrisch ansteuerbares Ventil bei einer positiven Differenz zwischen dem SOLL-Druck und dem IST-Druck; und
• (d) Entlüften des Luftbalgs über das Ventil bei einer negativen Differenz zwischen dem SOLL-Druck und dem IST-Druck. (Patentanspruch 6)

A method for Balgrestdruckregelung, in particular by means of a device according to any one of the preceding claims, comprising the following method steps:

• (a) determining an actual pressure in an air bellows of an air spring device;
• (b) comparing the ACTUAL pressure in the air bladder with a DESIRED pressure provided in an electronic memory device;
• (c) venting the air bladder via an electrically controllable valve with a positive difference between the DESIRED pressure and the ACTUAL pressure; and
• (d) venting the air bladder via the valve at a negative difference between the DESIRED pressure and the ACTUAL pressure. (Claim 6)

The inventive device and the invention has across from The above-described, known approach has the advantage that the Balgrestdruckregelung electronically, with different Balgrest pressure setpoints for different air suspension devices of a vehicle, for example on different axles or on different sides of the vehicle, independently can be programmed or parameterized from each other. Furthermore is also an automatic activation of the Balgrestdruckregelung at predetermined vehicle conditions possible. Furthermore it is possible, the respective predetermined bellows pressure with predetermined hysteresis curves over the To provide time.

The idea on which the invention is based essentially consists of detecting the actual pressure in an air bellows by means of a pressure detection device and comparing this with a parameterized nominal pressure, in dependence on an electrically controllable valve is actuated by the difference between the DESIRED pressure and the ACTUAL pressure to seal or aerate the air bladder to regulate the DESIRED value. Setting the ACTUAL pressure to the DESIRED pressure will result in too much and too little pressure in the air bellows and thus its damage. The DESIRED pressure can specify either a DESIRED pressure value or a pressure range with a maximum pressure and a minimum pressure, wherein both the DESIRED pressure value and the pressure range parameter can be dependent.

advantageous Refinements and developments of the invention are the dependent claims and the description with reference to the drawings.

According to one preferred development is the pressure detection device directly on the air suspension device, preferably a motor vehicle strut, or additionally or alternatively directly to a pressure supply line of the air suspension device arranged. By the spatial Proximity to Air bellows can be to ensure advantageously a fast and precise pressure detection.

According to one Another preferred development is at least one air suspension device at least one vehicle axle, preferably a truck and / or Semi-trailer or trailer axle, one Vehicle arranged. This has the advantage of a complete Balgrestdruckregelung the entire vehicle air suspension or even individual vehicle axles.

According to one Another preferred development is the valve as digitally controlled formed electrical slide valve, which in relation to the Actual pressure in the bellows with a pressure source, preferably one Accumulator or a pressure pump, and a pressure sink coupled is. A controllable by simple means valve is thus advantageous provided in pulses with predetermined valve opening times can be controlled.

In an advantageous embodiment, the valve by electronic and / or optical signals is driven. In particular, that will Valve controlled by digital signals.

According to one Another preferred development of the target pressure in response to an automatic or manual activation of a bellows pressure control device specified. Thus, the target pressure is variable and can also be automated be specified for Balgrestdruckregelung.

According to one Another preferred development is the activation of Balgrestdruckregelung at predetermined vehicle conditions an air-suspended vehicle, preferably vehicle-axle-selectively, automatically. In dependence of Vehicle states, which signal, for example, a loading or unloading of the vehicle is accordingly advantageous the bellows pressure control is activated automatically.

According to one Another preferred development is at least one predetermined Condition by an activated ignition and an activation of a parameterizable special module and / or a basic module and / or a rear module, preferably at a actuated Switch of a modular switching device, a vehicle, to automatic activation of the bellows pressure control defined.

According to one Another preferred embodiment is per vehicle axle, preferably per air suspension device, each with a separate parameterized one Target pressure corrected. This has the advantage of an individual Adjustment of the Restbalgdruckes, which for example in a Inclination of the vehicle around the vehicle's longitudinal or vertical axis when or unloading may be required.

According to one Another preferred development of the actual pressure within predetermined hysteresis times to the target print customized. This advantageously ensures that a gentle approach to the target pressure without large pressure overshoot can be provided.

According to one Another preferred embodiment is per vehicle axle, preferably per air suspension device, in each case a predetermined pressure hysteresis and / or a predetermined pressure tolerance range during the compensation provided the Balgrestdruckes. This particularly advantageous measure ensures a precise one Adaptation of bellows pressures individual spring means, wherein due to the predetermined pressure hysteresis or predetermined Pressure tolerance ranges a hectic operation of the valve avoided can be and thus the life of the same is increased.

The Invention will be described below with reference to the schematic figures The drawings specified embodiments explained in more detail.

It show:

1 a schematic flow diagram of a Balgrestdruckregelung to explain a Embodiment of the present invention; and;

2 a schematic cross-sectional view of an air spring system for explaining an embodiment of the present invention.

In the figures of the drawing are the same or functionally identical elements and signals - if nothing another is indicated - with the same reference numerals have been provided.

In 1 FIG. 3 is a schematic flow diagram according to a preferred embodiment of the present invention.

By applying a predetermined potential 10 which, for example, when the ignition of a vehicle is applied to a predetermined terminal of a vehicle device, the basic requirements for the Balgrestdruckregelung be provided. This is followed by the activation of a switch-on 11 , For example, a modular switch box on which there is preferably a switch for the general activation or deactivation of the Balgrestdruckregelung.

If this switch is not activated, the bellows pressure control goes into a defined inactive final state 13 without making any regulatory interference with the pressure in an air bellows of a spring device. Is the switching device 12 activated, so is at point 14 Checked whether the activation function should be forwarded or not. This check of command forwarding 14 Preferably takes place via a basic module of the vehicle, which provides basic functions of the vehicle, or a parameterizable special module, which is programmable with certain functions for vehicle control, or otherwise.

This is followed by the query of a target print specification 15 , which is in particular a query whether the Balgrestdruckregelung is parameterized, ie in particular whether a DESIRED pressure value has already been forwarded to a control device, for example in a rear module of the vehicle. If this is not the case, ie if there is no desired pressure value on the basis of which a ball-gap pressure regulation could take place, the system preferably likewise assumes the defined inactive final state 13 , However, if the pressure READ value is available, an actual pressure detection is performed 16 , Preferably by means of a pressure measuring device, which in particular provides an actual signal proportional to the actual pressure electrical signal or an already digitally converted signal.

Based on the IST pressure detection 16 can then make a nominal-actual pressure comparison 17 respectively. This target-to-pressure comparison 17 is preferably provided by a difference between the nominal pressure and the actual pressure, either based on analog electrical signal quantities, such as voltages, or digital signal values. In this desired-actual pressure difference formation, a predetermined pressure tolerance interval is preferably provided, within which the pressure difference, despite small deviations in the positive as well as in the negative direction, leads to a zero pressure difference value.

If the difference between the setpoint and the actual value is positive, ie if the set pressure value is higher than the actual pressure value, the pressure increases 19 in Luftbalg, which in particular by ventilation of the pressure bellows by means of a pressure source, such as a pressure accumulator or a pump, bewerkstel Ligt can be. If the difference between the nominal pressure and the actual pressure is negative, ie if the actual pressure is higher than the nominal pressure, a pressure reduction in the pneumatic bellows, in particular by venting the pneumatic bellows, for example by releasing pressure into the environment or be ensured by the use of a suction pump. Both in the loading and in the venting of the air bladder predetermined ventilation or venting times are preferably maintained, which depend in particular on the respective pressure difference.

Then, preferably in parallel, there is an actual pressure detection 16 to ventilate 18 . 19 to be able to regulate the air bellows precisely until the pressure values match or are preferably within a predetermined pressure interval. Then is a controlled Balgrestdruck 20 reached. In this case, the control can be automatically deactivated so long as to prevent unnecessary control intervention until, for example, a vehicle state, such as a load state, changes again, whereupon the Balgrestdruckregelung preferably again automatically activated.

In 2 is roughly schematically illustrated an air suspension device for explaining a preferred embodiment of the present invention.

An air suspension device 100 . 101 consists of an air bellows 100 and a strut section located therein 101 , wherein the strut section 101 in the bellows 100 is arranged movable in the vertical direction. In 2 not shown are sealing elements, preferably bellows or bead-shaped, between the strut section 101 and the outer wall of the pneumatic bellows 100 to maintain a Luftbalgdruckes.

Via a pressure detection device 102 , Preferably an electronic differential pressure gauge, which a differential pressure between the ambient pressure and the Luftbalginnendruck, ie The actual pressure, measures, is preferably directly to the Luftbalg 100 coupled. The pressure detection device 102 but can also have a separate pressure-tight supply line with the air bellows 100 be connected or between a valve 103 and the bellows 100 be positioned. The valve 103 is preferably an electrically controllable slide valve, which is in particular digitally controlled and operable. Digital operable in this context means that the valve 103 only knows two opening states, namely fully open or closed pressure-tight.

Via a supply line 104 is the valve 103 both with a pressure source 106 as well as a pressure sink 106 connected. As a pressure sink on the one hand the environment is suitable, on the other hand, a pump which can generate negative pressure compared to the ambient pressure. As a pressure source, it is possible to use a pressure accumulator, which is optionally continuously refilled by a pump, or to use a pump in isolation. Via a connection device 105 , preferably an electrical or optical line, is that of the pressure detecting device 102 determined actual pressure to a control device (not shown) forwarded and compared there with a programmable or parameterizable setpoint value of Balgrestdruckes, the valve 103 for ventilation of the air bellows 100 is controlled as a function of the difference between the nominal pressure value and the actual pressure value.

When Balgrestdruckregelung is activated in a vehicle with multiple controllable air-sprung facilities, the parameterized DESIRED pressure values on the one or more front and / or rear axles, preferably as with reference to 1 explained, corrected. In a separation of the air pressure system between the left and right side of the vehicle these separate pressure preset values can also be controlled separately. Preferably, a hysteresis and / or tolerance of the temporal pressure control and / or the tolerance range of the difference between nominal pressure and actual pressure is separately provided for the parameterized pressure values for the front and / or rear axles.

Becomes preferably each separately programmed or parameterized Bellows pressure over- or falls below, takes place within predetermined hysteresis times a venting or venting process, so that the parameterized nominal pressure is corrected. The manual Raise / lower a level control of the air spring device of Vehicle is not possible with active Balgrestdruckregelung. The Deactivation of the Balgrestdruckregelung can for example via a Buttons, such as a stop button, or a switch, such as PTO ON / OFF, done. With deactivated bellows pressure control is the normal level control again active or activatable.

Even though the present invention above based on preferred embodiments It is not limited to this, but in many ways modifiable. Although above primarily with respect to trucks in particular, the present invention is also described any vehicles applicable.

Claims (14)

Apparatus for controlling the pressure of bellows, in particular for air-suspension vehicles, comprising: an air spring device ( 100 . 101 ) for the resilient mounting of loads, which an air bellows ( 100 ) having; a printing technology with the air bellows ( 100 ) coupled, electrically controllable valve ( 103 ) for sealing or for aeration or venting of the air bladder ( 100 ); a printing technology with the air bellows ( 100 ) coupled pressure sensing device ( 102 ) for detecting an actual pressure in the air bladder ( 100 ); and an electronic control device for actuating the valve ( 103 ) as a function of the difference between a stored nominal pressure and the actual pressure. Apparatus according to claim 1, characterized in that the pressure detecting device ( 102 ) directly on the air spring device ( 100 . 101 ), Preferably a motor vehicle strut, is arranged. Apparatus according to claim 1, characterized in that the pressure detecting device ( 102 ) directly on a pressure feed line of the air spring device ( 100 . 101 ) is arranged. Device according to one of the preceding claims, characterized in that at least one air spring device ( 100 . 101 ) is arranged on at least one vehicle axle, preferably a truck and / or semi-trailer or trailer axle of a vehicle. Device according to one of the preceding claims, characterized in that the valve ( 103 ) is designed as a digitally controlled electric slide valve, which in relation to the actual pressure in the pneumatic bellows ( 100 ) with a pressure source ( 106 ), preferably a pressure accumulator or a pressure pump, and a pressure sink ( 106 ) is coupled. A method for Balgrestdruckregelung, in particular by means of a device according to any one of the preceding claims, with the following Verfah (e) determining an actual pressure in an air bladder ( 100 ) an air spring device ( 100 . 101 ); (f) comparing the ACTUAL pressure in the air bladder ( 100 ) with a DESIRED print provided in an electronic storage device; (g) aerating the pneumatic bellows ( 100 ) via an electrically controllable valve ( 103 ) at a positive difference between the DESIRED pressure and the ACTUAL pressure; and (h) venting the air bladder ( 100 ) over the valve ( 103 ) at a negative difference between the DESIRED pressure and the ACTUAL pressure. Method according to claim 6, characterized in that the valve ( 103 ) is controlled by electronic and / or optical signals. Method according to one of the preceding procedural claims, characterized in that the valve ( 103 ) is controlled by digital signals. Method according to one of the above method-related Claims, characterized in that the DESIRED pressure in dependence from an automatic or manual activation of a bellows pressure control device is given. Method according to claim 9, characterized in that that the activation of the Balgrestdruckregelung at predetermined vehicle conditions an air-suspended vehicle, preferably vehicle-axle-selectively, automatically done. Method according to claim 10, characterized in that that at least one predetermined state by an activated ignition and an activation of a parameterizable special module and / or a Basic module and / or egg nes rear module, preferably at an actuated switch a modular switching device, a vehicle's automatic activation the bellows pressure control triggers. Method according to one of the preceding method-related claims, characterized in that per vehicle axle, preferably per air suspension device ( 100 . 101 ), in each case a separate parameterized nominal pressure is corrected. Method according to one of the above method-related Claims, characterized in that the actual pressure within predetermined Hysteresis times adapted to the nominal pressure. Method according to one of the preceding method-related claims, characterized in that per vehicle axle, preferably per air suspension device ( 100 . 101 ), in each case a predetermined pressure hysteresis and / or a predetermined pressure tolerance range in the adjustment of the Balgrestdruckes is provided.